sodium tetrahydroborate in water; isopropyl alcohol T=0°C; 1 h;

1: 86 percent / 70percent HF / CH2Cl2; pyridine / 1.) 0 deg C, 1 h, 2.) room temp., 1 h 2: 74 percent / NaBH4 / propan-2-ol; H2O / 1 h / 0 °C View Scheme

1: 70 percent / t-BuOK / 2-methyl-propan-2-ol / Ambient temperature 2: 86 percent / 70percent HF / CH2Cl2; pyridine / 1.) 0 deg C, 1 h, 2.) room temp., 1 h 3: 74 percent / NaBH4 / propan-2-ol; H2O / 1 h / 0 °C View Scheme

jones reagent in acetone T=0°C;